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📚 DISTINCT

The DISTINCT keyword is used in SQL to return only unique values by removing duplicates from the result set.
It ensures that each returned row is different from the others.

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🛠️ Basic Syntax

SELECT DISTINCT column1, column2, ...
FROM table_name;

• SELECT DISTINCT removes duplicate rows based on the specified columns.
• All columns listed after DISTINCT are considered when checking for duplicates.

Example

SELECT DISTINCT department
FROM employees;

• This query returns a list of unique departments from the employees table.

Key Points

• DISTINCT applies to all the columns listed in the SELECT statement.
• If you select multiple columns, DISTINCT keeps unique combinations of all selected columns.
• You can use DISTINCT with aggregate functions in some databases (e.g., COUNT(DISTINCT column_name)).

Additional Example

SELECT DISTINCT city, state
FROM customers;

• This query returns unique combinations of city and state from the customers table.

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🎥 Video Notes

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📝 Problem Description

Describe the problem, challenge, or topic discussed in a video related to SELECT FROM.
What concept was explained or what exercise was solved?

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DataBase Given

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💻 My SQL Code

-- Write your SQL code attempt or solution related to SQL COMMAND
SQL COMMAND

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🧠 Solution Code / Explanation

SQL COMMAND

Explanation - Explain what you learned, any key takeaways, or how you solved the problem related to COMMAND._

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